Bug #17763 Updated: Interpretation of the term "multi-dimensional array"

ID: 17763 Updated by: jmcastagnetto@php.net Reported By: kristian.raue@gmx.de Status: Assigned -Bug Type: Documentation problem +Bug Type: Feature/Change Request Operating System: all PHP Version: 4.2.1 Assigned To: jmcastagnetto New Comment: If you really consider this array behaviour would be a "good thing" then do not submit it as a documentation bug, but as a feature request. Personally I do not think this type of data structure slicing is difficult to implement with a simple loop in PHP, or with a Matrix extension in C (see GSL for example). I will reclassify this as a feature request, and see if someone from php-dev decides to do something about this in the code, or just close this report. Previous Comments: ------------------------------------------------------------------------ [2002-07-01 13:20:16] m.ford@lmu.ac.uk Well, I think I'd agree with "nested array" and "multi-dimensional array". As for supporting the behaviour, this may (or may not!) be what you're looking for: In FORTRAN 9x if you declare a 2-dimensional array as: INTEGER, DIMENSION(2:5, 3:10) :: values then you can refer to (for example): values(2,:) ! retrieve first row values(:,3) ! retrieve first column Similarly, in Algol68 you can declare: [2:5, 3:10] INT values; and refer to: values[2,] # retrieve first row # values[,3] # retrieve first column # I'm not sure, however, if any of this is relevant, since both these examples of column-slicing apply to multi-dimensional arrays; personally, I wouldn't *expect* this kind of functionality with nested arrays, simply because they are arrays *of* arrays, and not monolithic multi-dimensioned ones. (In Algol68, it is also possible to declare an "array of arrays", but, from my dim, distant and exceedingly imperfect memory, I don't think you can "column"-slice those in the same way!) Cheers! Mike ------------------------------------------------------------------------ [2002-07-01 10:43:52] kristian.raue@gmx.de You are right, "multi-dimensional matrix" is propably a more precise term of what I meant. I don't know of a language that supports this behavior in their *native* array support and I don't have any example C code which can implement such constructs. ------------------------------------------------------------------------ [2002-06-18 10:22:23] jmcastagnetto@php.net Assigning to myself, while waiting for feedback ------------------------------------------------------------------------ [2002-06-17 18:24:53] jmcastagnetto@php.net Of the scripting languages I've used (Perl, Awk, Python), as well as some programming langs, usually what you call 'nested array' is referred to a 'multi-dimensional array' (sometimes interchangeably). What you are call 'multi-dimensional array' I would think more of a 'multi-dimensional matrix', which is a totally different concept, and no language I know supports such a structure like that natively. SciPython has support for matrices, and so do some Java libs, etc. If you know of a language that supports the behavior you point of in their *native* array support, I would like to learn. It will be even more usefule if you got some example C code which can implement such constructs, a patch to php4/ext/standard/array.[ch] will be the ultimate "good thing". Waiting for feedback ------------------------------------------------------------------------ [2002-06-14 09:41:46] kristian.raue@gmx.de Hello I think the term "multi-dimensional array" might be misleading for some people. Wouldn't "nested array" be more precise? Look at the following sample: $myArray = array( "A"=>Array("1"=>"test","2"=>"test","3"=>"test"), "B"=>Array("1"=>"test","2"=>"test","3"=>"test"), "C"=>Array("1"=>"test","2"=>"test","3"=>"test")); In this sample I can "unset($myArray["B"])" which deletes a elements associated with the key "B", but there is no function to delete all elements which are associated with the key "2" in one step. I have to go through all the elements of the ABC-Array and delete each "2"-Element seperatly. In a multi-dimensional array you could delete (and add)Elements in both dimensions without having to loop through the nested arrays. PS: I very much like the way PHP organizes Arrays, don't change it. It is just the term that confuses me. With Regards Kristian ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=17763&edit=1